Method and apparatus for forming web material



Sept. 22, 1936. E. HURST El AL METHOD AND APPARATUS FOR FORMING WEB MATERIAL Filed May 17, 1935 3 Sheets-Sheet l I I I I I l l I l l I l I I I I I I I I I I I F l I I l l l I I l I I l I I l I I I l I I I I I l I I l I I I l I I I I I II ATTORNEYS.

Sept. 22, 1936. E. HURST ET AL 2,055,412

METHOD AND APPARATUS FOR FORMING WEB MATERIAL Filed May 1'7, 1935 3 Sheets-Sheet 2 m-*y;-w F W W 5 M M 7 61* j ig ATTORNE 5.

Sept. 22, 1936. E, HURST H M 2,055,412

METHOD AND APPARATUS FOR FORMING WEB MATERIAL Filed May 1'7, 1935 3 Sheets-Sheet 3 v INVENTORJ.

ATTORNEYS Patented Sept. 22, 1936 UNITED STATES METHOD AND APPARATUS FOR FORMING WEB MATERIAL Edward Hurst and lvlyrick Crane, Fall River, Mass" asslgnors to United Cotton Products Company, Fall River, Mass, a corporation 01' Massachusetts Application May' 17, 1935, Serial No. 21,947

20 Claims. (01. 19155) This application is a continuation in part ofdivisional subject matter in our copending application Ser. No. 673,392, filed May 29, 1933, and relates to a novel and improved method for making the product claimed in said copending application as well as to a novel and improved apparatus for practicing that method.

In the accompanying drawings, we have illustrated one apparatus by which the method may be practiced, and have also illustrated certain other steps of the method. In those drawings:

Fig. 1 is a plan view of a portion of a floor upon which certain of the apparatus may be mounted and showing the relation of certain pieces of apparatus to each other;

Fig. 2 is a vertical sectional view along the line 2-2 of Fig. 1;

Fig. 3 is a view on the same plane as that of Fig. 2, but on an enlarged scale, showing certain parts of the apparatus in greater detail;

Fig. 4 is a section on the line 4-4 of Fig. 3;

.Fig. 5 is a view on the same plane as Fig. 3 but on a still larger scale and showing further details of construction;

Fig. 6 is a view on the line 6-6 of Fig. 3;

Fig. 7 is a perspective view on an exaggerated scale showing a small part of the web formed by our method before the web is impregnated;

Fig. 8 is a view on a similar scale to that used in Fig. 7, illustrating diagrammatically how the different membranes or laps are brought together by our method;

Fig. 9 is a section on the line 9--9 of Fig. 3.

In the making of the novel material as set forth in our aforesaid copending application, various fibrous materials may be employed, but for the sake of convenience of illustration we shall assume that the material used is cotton. In actual practice, we have used long fiber, American cotton with satisfactory results, and therefore, without intending to limit ourselves in any Way, we will proceed with the description of our invention when using cotton.

In Figs. 1 and 2 we have shown a portion of the floor l, which may be one of the floors of a mill, and upon which are mounted cards 2 of any suitable construction. Such mechanisms are well known in the art of cotton preparation, and no detailed description thereof is deemed necessary. We believe it is sufficient to say that in ordinary mill practice cotton leaves a card in the form of a light, filmy lap or membrane of unspun fibers, being removed from the doffer 3 by a comb l. Ordinarily, the lap is then passed through a trumpet to form a sliver from which yarn is formed. According to our invention, however, the trumpets are omitted and the lap from any one card is led directly from the comb downwardly through an orifice in the floor, while undergoing treatment more fully described later. In this instance, four cards are shown, having their longitudinal axes parallel to but ofiset from each other laterally of the cards, as will be plain from an inspection of Fig. l. The laps 5, 6, I, and 8, respectively, are shown passing through orifices 9 in the floor, all of the same general construction, and the form of which is more fully described later.

As indicated by the arrows in Fig. 2, a light current of air is caused to flow against the movement of the conveyor and against the movement of the laps or membranes through the respective orifices 9. As noted above and as known in the art, the laps are very light in character, and the light currents of air contacting with the fibers of the laps will cause a displacement and loosening and consequent rearrangement of the individual fibers in each lap as it passes through one of the orifices, while maintaining the continuity of the lap. The orifices may be made of the stream-lined form shown, without sharp corners, and are indicated as of a general Venturi shape, which shape aids in the displacement of the fibers and the loosening up of the lap, or they may be made in the form shown in the copending application of Edward Hurst, Ser. No. 722,868, filed April 28, 1934, in which the action taking place in the orifice is more fully described and claimed. By the above described orifice construction and control of air currents, each membrane is maintained out of engagement with the orifice edges, as indicated. Preferably, the space A, in Fig. 9, is greater than, or at least as great as, the space E.

Beneath the floor I, and shown as running substantially horizontally, is an endless conveyor designated generally as l and which will be described more in detail presently. The cards are arranged above this conveyor and spaced apart longitudinally thereof. The longitudinal axes of the cards are those axes extending lengthwise of the conveyor and, as plainly seen in Fig. 1, these longitudinal axes are disposed generally parallel to the longitudinal axis of the conveyor, but offset from each other laterally of the conveyor.

The result of this arrangement is probably best evident from an inspection of Fig. 6, in which it will be seen that the conveyor has its upper reach ll extending between vertical guides ll. Initially, in starting operations, the lap is first led by hand carefully through the first orifice 9 and deposited upon the upper reach of the conveyor. In the arrangement shown, the lap is offset laterally from the center of the conveyor, and it is shown as being led to the conveyor adjacent the center thereof.

As just noted, the lap 5 is offset laterally from the center of the conveyor, since the orifice 9 through which that lap passes is thus offset. The light filmy lap or membrane is carefully led, however, to a position adjacent the center of the conveyor, which thus causes a displacement of the membrane or lap transversely of the length of the conveyor. The fibers of the lap have been interlocked to a sufflcient extent, to establish a continuity in the lap, and as this lap drops through its orifice 9 upon the conveyor, it is continuously drawn towards the center of the conveyor.

Then similarly the next lap 6 is led through its orifice and likewise started on top of the lap 5, which is already on the conveyor. The same pro- ,cedure is followed with the laps I and 8, and it will be seen that, as each lap reaches the conveyor, it is displaced laterally of itself, so that the fibers in that particular lap which the card has initially caused to extend generally parallel to the length thereof and which may not have been disturbed by the air currents, will be caused to be deposited on the conveyor diagonally to the length thereof. Similarly, the fibers in a lap which have been displaced and rearranged by previous contact with air currents, as described above, will be disposed at various angles to the fibers of adjacent laps on the conveyor, thus aiding still further in causing the fibers of one lap to interlock with those of another. Nomatter what may be the position of the fibers in a lap, the feeding of the lap to the conveyor from an offset position, as described above, has been found to aid in blending the various laps together. This may be caused by arrangements differing somewhat from what we have shown herein, and the amount of the ofisets between adjacent cards will, of course, vary with different conditions. Ordinarily, a lateral displacement or offset of a few inches between adjacent cards is sufiicient for our purpose.

The conveyor is preferably operated so that the upper reach thereof is moving at substantially the same speed as the membranes when they come in contact with the conveyor and are deposited thereon. The upper reach is preferably given a continuous, gentle vibration vertically, and the upper surface of the conveyor may be uneven if desired.

As'the first membrane 5 travels along the conveyor, it is thus shaken up by the vibration and the fibers further rearranged at various angles, although, under most conditions, it will be found desirable to not rearrange the fibers to such an extent as to have them extending at right angles to the length of the web. In other words, for most purposes, it is best to rearrange as many fibers as possible so that they will extend generally lengthwise of the web but at an acute angle to the longitudinal axis thereof. It will readily be understood, however, that the positions ofthe fibers will depend largely upon the use to which the conveyor, and in the presence of a lightcurrent of air, to the action of which, as stated above, the membrane has been subjected since it left the card, the fibers of a membrane reach a semisuspended condition so that by the time the second membrane 6 is deposited thereon, the fibers interlock with those of the first membrane. The operation will be continued while the third or any subsequent membranes are deposited on the traveling web.

In this semi-suspended condition of the fibers in each membrane, they are in an unmatted state and are deliberately displaced from the positions which they occupied as they left the card. This rearrangement which they have undergone is partially in a direction normal to the surface of the lap, the position of a fiber being a predetermined and definite one, as the result of the action to which it has been subjected. Therefore, when two or more membranes are brought together, these membranes will readily blend or unify, as just noted above, by definite interengagement or interweaving of the fibers in adjacent membranes. A large number of fibers in a membrane will project outwardly from the surface of that membrane, at various and definite angles thereto, and will actively interweave with the fibers in an adjacent membrane.

By the time the membranes reach the end of the conveyor, the individual membranes have become blended in a single web, because of the interengagement and interweaving just mentioned, which is aided by the action of the conveyor, described above. This single web is still light in weight and without substantial tensile strength. The web l2 formed by the membranes is now permitted to pass downwardly through guide rolls l3, these rolls, however, exerting no pressure at all upon the web.

In Fig. 8 I have shown two membranes 5 and B in very diagrammatic form, indicating mostly the fibers which extend transversely to the planes of the membranes and indicating that since a large number of the fibers thus extend transversely to these planes, they may easily interlock without any pressure whatsoever. In Fig. 8, the membrane 5 is shown as if it were resting upon the upper reach of the conveyor, and the membrane 6 is coming down through its orifice 9 upon the top of the membrane 5. Its fibers then will interlock with the fibers of the membrane 5, and this action is increased because of the fact that the membrane 5 has been placed upon the conveyor from a difi'erent position than the membrane 6, and further by the fact that the upper reach of the conveyor is being vibrated.

In Fig. 6 we have shown how the several membranes are brought together adjacent the center of the conveyor from positions situated at one side of the center. The membranes are of such extremely light character that no specific guiding means is necessary to guide them from the orifices to the conveyor, it merely being necessary for the membranes to be properly started on the conveyor as the operation starts. Then the interlocking of the fibers of adjacent membranes causes the membrane or membranes that are on the conveyor to pull the succeeding membranes sidewise so that they all are bounded by the same lateral limits. By properly regulating the speed of travel of the conveyor, the material on the upper reach of the conveyor will move at substantially the same speed as the membranes coming through the orifices 9, and therefore the membranes keep be used if found desirable. While all the membranes are shown as being deposited on the conveyor, it is possible, under some circumstances, to lead one or more directly to a part of the web previously formed, between the end of the conveyor and the rolls II. V For example, in Fig. 2, the membrane 8 is shown as being deposited on the conveyor closely adjacent the end thereof so as to blend with the other membranes on the conveyor to a certain extent, although,'obviously, this extent is alimited one. 5 h

We have also shown a fifth membrane 8' which is not deposited on the conveyor at all, this membrane being formed in a manner similar to'the other membranes. In Fig. 3 this additional membrane 8 has been omitted. Byproviding a suitable vertical distance between the end of the conveyor and the rolls l3 and properly controllin the currents of air, it is possible ,"to thus blend one or even a plurality of membranes, with the laps already blended on the conveyor.

In any case, the result is a homogeneous web in which the fibers are interwoven and interengaged in a multiplicity of planes in which they have been deliberately placed. In this web there are no laminations as is the case when a pinrality of laps are brought together by the various methods of the prior art. The web is of substantially uniform character throughout, whereas the prior art webs may be separated into their laminations.

After leaving the rolls I 3, the web is then passed back and forth through rolls N arranged at successively lower levels. These rolls likewise exert no pressure upon the web and are preferably all driven at the same speed as the web, as are also the rolls l3, so as toavoid any tension being placed upon the web.

The back and forth or alternate bending of the web by the rolls I4 serves to alternatelylengthen and contract opposite sides of the'web, and this action seems to aid in blending the membranes together into one unlaminated and unfelted web. From the lowermost roll I, the web is now conducted downwardly to an impregnating device l5. This devicemay comprise a vat i6 containing a latex glue, the level of which is indicated at ll. A lower roll I8 rotates in the liquid, and the web is pressed between that roll and the upper roll it), this being the first step at which pressure of any kind is permitted to be exerted on the web. Preferably, these two rolls are driven together at'substantially the same speed as the speed of the web passing therebetween. y

After leaving the impregnating device, the web is dried, and for this purpose we have shown diagrammatically a festoon drier consisting of a plurality of roll supports 20 over which the web may be continually fed directly from the impregnating device. Other suitable drying arrangements may, of course, be used as found suitable.

In applying the latex glue or other materialto the web, care should be taken to avoid contact of the web with the lower wetting roll i8 until it reaches the throat between the two rolls l8 and i9. Similar care should be exercised to prevent the web from remaining in contact with the lower roll after passing through that throat. For that purpose, the parts of the apparatus are soarranged with respect to each other that the web is led downward at such an angle that it will contact with the upper pressure roll I! and by it be guided through the throat between that roll and the wetting roll. The web, after passing through that throat, is again led upwardly so as to follow around the pressure roll I! rather than the wetting roll' ll. Both rolls have blotting surfaces which may conveniently be formed by several layers of cheese-cloth, to take up the excess of the impregnating material.

It will be noted that the laps or membranes and the web into which they are formed are free of tension of any kind and are also free of pressure-until they reach the impregnating device. At no time is the web or one of the laps forming it caused to move upwardly, the movement always being either horizontal or in a downward irection. Therefore the force of gravity is never permitted to exert any tension upon the web or the parts thereof.

' 'As also noted above, the conveyor and also the rolls l3 and H are all operating at such speeds that .;the parts thereof contacting with the web or its parts are moving at the same speed as the web tion which will give the results set forth above,

but one form which we have used comprises a plurality of longitudinally extending narrow belts 2i (Figs. 4 and 5) connected together by transversely extending tie bars 22. Secured to the tie bars is a sheet 23 shown as having an uneven surface which may be obtained, for example, by not stretching the sheet tight. The vibration of the conveyor may be obtained by any suitable means.

In this instance, it is shown as being obtained by the fact that the rivets which secure the bars 22 to the belts 2| have heads 24 which project beyond the belts. The belts pass over rolls 25 at opposite ends of the conveyor, and when these rivet heads 24 engage and disengage the rolls, the conveyor is given an agitation which we have found serves the purpose.

The impregnating material is preferably a latex glue, such as is commonly known and which needs no further description. The glue may be diluted or not, and the amount of dilution may be varied between quite wide limits, all depending upon the results which it is desired to obtain and upon other factors, as will, of course, be obvious to those skilled in the art.

After leaving the impregnating device, the web is still wet and, as pointed out above, should be dried. It is still lacking in strength, although appreciably stronger than before impregnation. This strength, however, increases as it becomes drier. After drying, it will be found that the resulting web is one in which large numbers of fibers instead of, being generally parallel to the length of the web as in the laps provided by the several cards, are arranged diagonally to the length of the web in such a way as to form a multiplicity of polygonal-shaped and usually diamond-shaped figures, and with a large number of those figures, the polygon formed by fibers decontact with each other and in the presence fines a hole extending through the web from side to side. The fibers are thoroughly impregnated with and held together by the latex glue which acts as a binder to hold the fibers together.

The fibers are likewise interlaced, interwoven, .or interlocked into a substantially homogeneous structure which is free of laminations and is unfelted and unmatted. The relation of the fibers to each other is indicated roughly in Fig. 7, wherein is shown a perspective view of a piece of the web made by the joining together of several membranes as described above.

In that figure it will be seen that the fibers of cotton of which the web is preferably made are interwoven or interlocked in a multiplicity of non-parallel planes throughout the extent of the web, so as to form a woven fabric. That is to say, in any one of the usual three geometrical reference planes X, Y, and Z, may be seen an interweaving or interlocking, and such action is not limited by any means to those three planes. While this figure represents a web formed of the interweaving of four different membranes, nevertheless it will be seen that there is absolutely nothing todetermine where one membrane stops and another begins, because of the uniform interlocking or interweaving of the fibers of the respective membranes, which causes them to form one web, of substantially uniform character throughout, and formed of fibers woven together into a fabric.

While we have shown a certain specific form of apparatus for practicing our method, and have described one method in considerable detail, of course it is' to be understood that various changes in the apparatus and in the method may be made without departing from the invention asdefined by the appended claims.

We claim:

1. The method of forming a web which comprises forming a plurality of laps of fibrous material, placing the laps one on top or the other and approximately within the same lateral limits from positions displaced laterally of the laps with respect to eachother, agitating said laps in of a light current of air passing thereover to form the fibers into a non-laminated web, bending said web first in one direction and then in the other out of its plane, and then impregnating the web with an elastic material.

2. The method of forming a web which comprises forming a plurality of laps of fibrous material, placing the laps one on top of the other and approximately within the same lateral limits from positions displaced laterally of the laps with respect to each other, gently agitating said laps while in contact with each other, bending said web first in one direction and then in the other out of its plane, and then impregnating the web with an elastic material.

3. The steps in the method of forming a web which comprise forming a lap of fibrous material, and rearranging the fibers in the lap by passing it through an orifice against a current of air flowing through said orifice.

4. The method of forming a web which comprises forming a plurality of laps of fibrous material, passing each ofsaid laps through an orifice against a gentle current of air, laying said laps one on another on a conveyor traveling at approximately the same speed as said laps when they reach the conveyor, subjecting the laps on the conveyor to a gentle current of air flowing-in the opposite direction to the travel of the conveyor, and gently agitating the conveyor to work the fibers of the laps together.

5. The method of forming a web which comprises forming a plurality of laps of fibrous material, laying said laps one on another on a conveyor traveling at approximately the same speed as said laps, subjecting the laps on the conveyor to a gentle current of air flowing in the opposite direction to the travel of the conveyor, and gently agitating the conveyor to work the fibers of the laps together.

6. In combination, a horizontally extending conveyor, a plurality of cards disposed above said conveyor and spaced longitudinally thereof and arranged to discharge their laps on to said conveyor, said cards having their longitudinal axes extending lengthwise of the conveyor but offset with respect to each other laterally of the conveyor, and means to give said conveyor a continual vibration during the movement thereof.

7; In combination, a horizontally extending conveyor, a plurality of cards disposed abovesaid conveyor and spaced longitudinally thereof and arranged to discharge their laps on to said conveyor, means to give said conveyor a continual vibration during the movement thereof, and

a plurality of rolls arranged atsuccessively lower levels than the conveyor to successively engage the web after it leaves the conveyor and said rolls being so arranged as to exert substantially no pressure upon the web passing thereover but to after it leaves the conveyor and said rolls being so arranged as to exert substantially no pressure upon. the web passing thereover but to repeatedly change the direction of travel of the web, and an impregnating device adapted to receive said web after it leaves said rolls and disposed at a lower level than said rolls. 9. The method of forming a web which comprises forming a plurality of laps of fibrous material, passing each of said laps through a Venturi-shaped orifice against a gentle current of air, laying said laps one on another on a conveyor traveling atapproximately the same speed as said laps when they reach the conveyor,-subjecting the laps on the conveyor to a. gentle current of air flowing in the opposite direction to the travel of the conveyor, and gently agitating the conveyor to work the fibers of the laps together.

10. The method of forming a web which comprises forming a plurality of laps of unspun fibers, bringing said laps into contact with each other in a web, without pressure, and bending said web, first in one direction and then in the opposite direction without pressure to cause the fibers of v the laps to interengage with each other, and imthe laps are discharged therefrom frompositions I 2,055,412 which are offset with respect to each other lat' erally of the conveyor.

12. In combination, a horizontally extending conveyor, a plurality of cards disposed above said conveyor and spaced longitudinally thereof, and means to discharge laps from said cards on to said conveyor, said cards having their longitudinal axes approximately parallel to the longitudinal axis of the conveyor but offset with respect to each other laterally of the conveyor, whereby laps from said cards are discharged. on to said conveyor from positions which are ofiset with respect to each other laterally of the conveyor.

13. In combination, a horizontally extending conveyor, a plurality of cards disposed above said conveyor and spaced longitudinally thereof and arranged to discharge their laps on to said conveyor, means to give said conveyor a continual vibration during the movement thereof, and a plurality of rolls, at least some of which are arranged at successively lower levels than the conveyor, to successively engage the web after it leaves the conveyor and said rolls being so ar ranged as to exert substantially no pressure upon the web passing thereover but to repeatedly change the direction of travel of the web.

14. The method of forming a web which comprises forming a plurality of laps of unspun fibers, and placing said laps one on top of another on a conveyor and approximately within the same limits as measured laterally of the conveyor, from positions spaced along the conveyor and each of which is displaced from another one of said'positions laterally of the conveyor, whereby fibers of one lap will be disposed at angles to those of another lap.

15. The method of forming a web which comprises forming a plurality of laps of unspun fibers, placing said laps one on top of, another on a conveyor and approximately within the same limits as measured laterally of the conveyor, from positions spaced along the conveyor and each of which is displaced from another one of said positions laterally of the conveyor, whereby fibers of one lap will be disposed at angles to those of another lap, and during said placing of the laps on the conveyor passing into contact with a lap a current of air under such pressure as to rearrange fibers within the lap without substantially disturbing its continuity.

16. The method of forming a web which comprises forming a plurality of laps of unspun fibers,

placing said laps one on top of another on a conveyor, and approximately within the same limits as measured laterally of the conveyor, from positions spaced along the conveyor and each of which is displaced from another one of said positions laterally of the conveyor, whereby fibers of one lap will be disposed at angles to those of another lap, and then subjecting the contacting laps to the passage of a light current of air.

17. The method of forming a web which comprises forming a plurality of laps of unspun fibers, placing said laps one on top of another on a conveyor, and approximately within the same limits as measured laterally of the conveyor, from positions spaced along the conveyor and each of which is displaced from another one of said positions laterally of the conveyor, whereby fibers of one lap will be disposed at angles to those of another lap, and gently agitating said contacting laps.

18. The method of forming a web which comprises forming a plurality of laps of unspun fibers, placing said laps one on top of another on a conveyor, and approximately within the same limits as measured laterally of the conveyor, from positions spaced along the conveyor and each of which is displaced from another one of said positions laterally of the conveyor, whereby fibers of one lap will be disposed at angles tothose of another lap, gently agitating said contacting laps and in the presence of a light current of air passing thereover, thus forming a non-laminated web, and treating said web with an impregnating material.

19. The method of forming a web which comprises forming a plurality of laps of unspun fibers, placing said laps one on top of another on a con-- veyor from positions spaced along said conveyor, and giving said conveyor a continual gentle vibration during the movement thereof, while passing a light current of air over the contacting laps on the conveyor and the laps being fed thereto.

20. The method of forming a web which compassing into contact with said laps currents of air under such pressure as to rearrange fibers within the laps without substantially disturbing their continuity, bringing said laps into contact with each other in a web, without pressure, and bending said web, first in one direction and then in the opposite direction without pressure to cause the fibers of the laps to interengage with each other, and impregnating the web thus formed with an adhesive.

EDWARD HURST.

MYRICK CRANE.

prises forming a plurality of laps of unspun fibers, 

